Welt insole and preformed sewing rib therefor



Aug. 8, 1944. w. c. WRIGHT 5,

. WELT INSOLE AND PREFORMED SEWING RIB THEREFOR Filed March 17, 1943 Patented Aug. 8, 1944 UNITED srn'riazs PATENT OFFICE WEL'l INSOLE AND PREFORMED SEWING am THEREFOR 4 Claims.

My present invention is a novel and improved welt insole for use in the manufacture of boots and shoes, and is directed more particularly to an improved sewing sole. Heretofore in the manufacture of welt shoes,it has been customary to utilize an insole which is of sufficient thickness, or irons," to enable the edge portion to be split and a part of the insole to be turned upwardly to constitute a sewing rib or a part of such rib, and usually a channel was cut in the insole opposite the split portion, and the channeled part also turned up and incorporated in the sewing rib for stitch-retaining. strength Other efforts to utilize a sewing rib in an unrib incorporated with said inchanneled insole were to secure to the marginal edge of an insole blank 9, flanged tape, preferably enclosing a filler, and stitched or adhesively secured together. The welt insole was then tacked to the bottom of the last and the upper materials assembled, lasted, and secured to the insole by tacks or to the sewing rib by staples, and thereupon the inseam stitching was applied, uniting the sewing rib, upper materials, and welt .together. I In this prior practice it was difilcult, if not impossible, to have the upper materials, viz., upper and lining, snugly in contact with the sewing rib throughout im length, even when the, inseam stitching was set under considerable tension, as the upper would span the space between the outside edge or feather of the insole and the top of the rib, thus leaving a highly objectionable .groove or space at the base of the rib.-

thus eliminating the objectionable open groove or space heretofore found in welt footwear.

A further object of the invention is to providev a sewing rib construction which will be accurately preformed to facilitate lasting and inseaming, and to provide a proper angle or surface of substantial strength and rigidity to receive stapling and inseam stitching, the latter being usually set by a curved needle.

For the purposewf increasing the tightness of the seam and to facilitate the curved needle sewing, I provide a novel form and type of rib structure which can be secured to an insole blank adjacent the margin and with a predetermined inner bevelled or angular face to insure the stitching lying at the base ofthe rib, and with the opposite or outer surfaceoi' the rib at a predetermined angle to facilitate the penetration of the curved needleduring the inseam stitching,

and also with a portion of the rib of a contour to facilitate lasting and stapling.

In carrying out my invention, I provide a sewing rib with an attaching flange, preferably, of a mass of integral homogeneous material, such as either a molded or extruded plastic, which may be of continuous length and of predetermined contour, thickness, strength, and permanent resiliency, and can be readily attached to the marginal portion of the insole blank by adhesive or mechanical means. I find that standard types of material such as Koroseal, Vinylite, or the like can be used advantageously for this p rpose. By utilizing material of this type I am enabled to accurately preform the'oute'r and inner surfaces of the opposite faces of the rib and because of the novel contours accorded for stapling and stitching, I can utilize a relatively low rib in height, as the surface contours insure and facili tate accurate lasting, stapling, and stitching.

This also serves to eliminate to a large degree the trimming and waste material on the rib when the subsequent inseam operation is performed on welt footwear.

The outer edge surface of my novel rib has a fillet or extending flaLge-like contour projecting toward or adjacent the outer edge of the insole to which the rib is attached, thus permitting the v upper materials to be snuglydrawn into contact sewing rib to be positioned more closely adjacent the, edge of the insole than heretofore, if desired. as well as enabling the rib to be spaced from the edge and still enable a snug and tight-fitting of the upper thereto.

I also prefer to form the upper part of'the outer vertical face of the rib throughout its length in a position substantially perpendicular with the plane of the insole-to which the rib is attached to facilitate the stapling. Furthermore, I make the inner upstanding surface of the rib at an angle less than 90 relatively'with the surface-of the insole, thus giving an acute angled or bevelled surface to insure the inseam laying at the base of the rib and, furthermore. providing a considerable mass throughout the height and thickness of the sewing rib to withstand the lasting and stapling strains and give a substantial mass of material to which the upper is secured;

Thus a will be appreciated that my novel insole ,with the sewing rib having an inner acute angled bevelled face, and an outer face in the' form of a combined fillet or curve at the bottom, and a substantially perpendicular upper face, produces a rib with a broader mass of material widthwise at the top than at the bottom to secure the desirable results above briefly outlined. This feature of having the inner and outer vertical faces of the sewing rib at a relatively divergent angle so as to be broader at Referring to the drawing illustrating a preferred embodiment of the present invention:

Fig. 1 is a perspective view partly in crosssection showing my novel type of sewing rib on an enlarged scale;

Fig. 2 is a fragmentary view in cross-section of a side portion of the insole with my sewing rib attached adjacent the margin;

Fig. 3 illustrates in fragmentary view an insole on a last, with the upper and lining stapled to the sewing rib;

, Fig. 4 is a corresponding view showing the inseammg attaching the welt, and

Figs. 5 and 6 are diagrammatic views in crosssection illustrating prior sewing rib structures to distinguish over applicants improved and streamlined outer face with the diverging side faces on the rib.

Referring to Fig. 1, my sewing rib designated generally at I is preferably formed of a mass of permanently plastic material, such for example as numerous well known types of synthetic polyvinyl resins, which may be molded or extruded, and of a suitable consistency and toughness: to be stitch-retaining. I find that Koroseal, Vinylite,and similar materials may be utilized from which to make my novel preformed rib.

Preferably I also form integral with the sewing rib l a horizontal attaching flange 2, in order to facilitate the adhesive attachment of the rib to an insole blank 3. This attaching flange 2 may be and preferably is formed as a double rib structure, with-a series of zig-zag curves or lines. cutting the two rib portions apart, forming each asa separate rib structure, with the attaching flange pinked" as shown. The outer face of the rib has two surfaces, the lower curved or fillet portion 5 and an upper vertical, or substantially vertical, face 6; and the opposite or inner slopassassa angle relatively with the horizontal flange 2, thus giving a flaring or divergent structure to the rib in cross-section, with a substantial mass of material at the top. This gives added strength and resistance during lasting and stapling even though the rib itself is of pliable, permanently resilient material, such as the synthetic plastics above mentioned.

Preferably the rib is attached to the marginal portion of the insole with a fillet or curved part 5 adjacent or even in register with the extreme edge 8 of the insole, as shown in Fig. 2, thus giving a much closer and tighter edge to the insole and the resilient shoe structure than has heretofore been possible where a standard type of channeled or composite built sewing rib has been utilized, which latter types are shown in diagrammatic form in Figs. 5 and 6 for illustration. The fillet 5 may, of course, be either curved or straight as a part of the outer surface of the rib.

With the'insole assembledon a last Ill and the upper materials ,H and I2, viz., a lining and finished upper, the shoe is lasted in the usual manner and stapling or lasting fasteners H .are applied thru the upper and rib, the width and strength afforded by the mass of the rib constituting a good firm guiding element against which the lasting operation can be held and the stapling or other mechanical fasteners secured. Thereupon the welt is fltted and applied, and

the inseam stitching 20, which latter draws the upper flrmly against the fillet portion 5, thereby giving a firm solid bearing between the welt, upper materials, and sewing rib, and a contact of the upper substantially against the entire outer. face of the sewing rib I. The inner inclined surface 1 and the relatively wide and solid face of the. sewing rib gives a firm and ac- .40 curate guide for the inseaming machine during the seating of the inseam stitches 26, thus insuring a tight joint, better fitting, and good shoe-making, eliminating grinning of stitches along the forepart and toe of the shoe.

In Fig. 5 I have illustrated in fragmentary form a typical channeled insole 2| with'the edge portion split and turned up into a rib member 22, and with an inner channeled lip or rib 23 also cut and turned and joined together into a sewing rib against which the upper materials 24 and 25 are lasted and stapled. Owing to the length required to make the rib members 22 and and 23, the rib itself is a substantial distance back from theedge 26 of the insole, thus leav- 'ing a feather 21 and thereby also tending to leave an open channel or groove 30 throughout the entire length of the ribbed structure.

It is this channel or groove which is an object of my invention to eliminate. Such a rib is usually reinforced or gemmed by a strip of canvas 28, and the inseam stitching 3| draws the upper materials partly into and against the sewing rib but necessarily tends to leave an open spaceor channel 30, as above explained.

Similarly in Fig. 6 I have illustrated a prior rib structure comprising a fragmentary portion of the insole 33 and the sewing rib built of a filler 34 and a overlapping double flanged member 35, with flanges-36 and 31 secured to the.

ing face I is preferably formed at an acute, 16

face of the insole 33 by adhesive, stitching, or the like.

In this form, also, the upper materials 38 and -39 will tend to leave an open space or groove 40 at the base of the rib, which is objectionable. Both these prior constructions also required conan inwardly slanting surface, 1. e., inwardly tward the center of the insole to which the rib is attached, to facilitate the inseam stitching and guiding, together with the outer or opposite side face of the rib extending substantially perpendicular and, hence, at a divergent angle with the inner slanting face, and thus producing a somewhat flaring top thickness in the rib, is a distinct novelty in this art and I wish to claim the same herein broadly.

Also the preforming of such a molded rib structure with the opposite faces of the side walls from amass of plastic material having initial and permanent resiliency, together with toughness for stitch-retaining and sufficient strength to resist the lasting operations, stapling, or tacking and inseaming, is believed novel and is claimed broadly herein.

Also the fillet feature, permitting the sewing rib to be secured closely adjacent the edge of the insole, as well as at spaced or variably spaced positions throughout the forepart and toe portions, and heel if desired, provides an effective streamlining for snug and close fitting of the upper materials and welt, which are drawn into close contact with the fillet and rib during the inseaming operation. Heretofore, upstanding sewing ribs have usually had the side faces parallel and if the rib was slanted inwardly toward the center of the insole, as was desirable, the

outer surfaces of the rib would also slant inwardly, resulting in difficulty in lasting and Thus my preformed rib is self-sustaining and stitch-retaining independently of gemming or reinforcing strips or tapes, which latter are necessary where any rubber compound is employed and, of course, rubber quickly loses its strength and resiliency; whereas the synthetic resinous material such as Koroseal maintains its integrity both of strength and resiliency indefinitely, much longer than the life of the rest of the shoe materials.

I claim:

1. A welt insole for use in the manufacture of welt boots and shoes, comprising an insole blank of one material and a preformed sewing rib of difierent material having an integral at-' taching flange secured to the marginal portion of the insole, said rib being of resilient plastic material, and having its upper portion of greater thickness than at the base of the rib adjacent said flange. 4

2. A welt insole for use in the manufacture of welt boots and shoes, comprising an unchanneled insole blank and a separate preformed sewing rib having an attaching flange adhesively secured to the marginal portion of the insole, said rib being of resilient plastic material, and having the inner side face slanting upwardly and inwardly toward the center of the insole, and the outer face having a portion substantially perpendicular to the insole.

3. A welt insole for use in the manufacture of welt boots and shoes, comprising an insole blank and a preformed sewing rib secured to the marginal portion of the insole, said rib being of resilient plastic material, and having the inner side face slanting upwardly and inwardly toward the center of the insole, and the outer face having a portion substantially perpendicular to the insole, with the lower portion of the outer face in the form of a fillet.

4. A preformed rib of stltchretaining permanently resilient plastic material, having a horizontal attaching flange integral therewith, the inner face of the rib slanting over a portion of said flange, and the outer face of the rib having a substantial portion of its length perpendicular to the flange, and the lower portion of the outer facein the form of a fillet merging with the attaching flange.

WALLACE C. WRIGHT. 

